MVBS Inc. proposes to develop CATSIS, a simple, safe, and unobtrusive test that will screen patients in their homos for disordered breathing during sleep. The CATSIS system uses simple hardware to record a patient's tracheal breath sounds during sleep. These recordings are then analyzed by specially-developed software running on a mainstream personal computer, with the aim of quantifying the occurrence of apnea, hypopnea, and perhaps, wakefulness and heart rate. Like any screening test, the CATSIS results would then be factored into a decision about whether or not to perform the expensive 'gold standard' test, in this case, overnight polysomnography in a sleep laboratory.